This invention relates to phased-array semiconductor lasers produced by aligning a plurality of semiconductor lasers adjacent to one another and capable of obtaining a high output laser having a uniform phase as a whole.
Conventional phased-array semiconductor lasers have now attained a stage where the correlation of phases can be established between adjacent semiconductor lasers, and an output of about 500 mW can be obtained as described for example in prior art reference "Phased Array Diode Lasers" in the "Laser Focus", June, 1984. However, the far-field pattern is apt to become a double-lobe, and even if the beam having such a double-lobe intensity distribution is converged by an optical system of a laser printer or an optical disc, for example, an optical spot of a diffraction limit cannot be obtained and the ratio of optical utilization is at most about 50%.